MLA
L.L. Cook Co. (Milwaukee, Wis.). Owen Lovejoy Homestead Underground Station, Princeton, Ill.. unknown. Robert Langmuir African American Photograph Collection. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/68605qftx3-cor.
APA, 6th edition
L.L. Cook Co. (Milwaukee, Wis.). (unknown)[Owen Lovejoy Homestead Underground Station, Princeton, Ill.]. Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/68605qftx3-cor.
Chicago
L.L. Cook Co. (Milwaukee, Wis.), Owen Lovejoy Homestead Underground Station, Princeton, Ill., unknown, Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/68605qftx3-cor.